[BUG] RangeError: Invalid string length when processing large benchmark output

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Claude Code CLI crashes with RangeError: Invalid string length when processing large benchmark output from FluxMQ server. The CLI becomes completely
unusable and terminates with a JavaScript engine error.

What Should Happen?

Claude Code should handle large outputs gracefully, either by:

• Truncating very long outputs with a warning
• Streaming output in chunks
• Providing pagination for large responses
• Setting reasonable limits on output processing

Error Messages/Logs

RangeError: Invalid string length
      at file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1748:4370
      at file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:1829:3000
      at file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:2236:27268
      at yR (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:34:20239)
      at kR (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:34:20722)
      at Object.useState (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:34:27275)
      at T5Q.useState (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:10:7178)
      at R7 (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:2236:27156)
      at VC (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:34:19415)
      at Ry (file:///Users/sonheesung/.nvm/versions/node/v22.18.0/lib/node_modules/@anthropic-ai/claude-code/cli.js:36:3227)

  ERROR  Invalid string length

Steps to Reproduce

1. Run a command that generates extensive output (1000+ lines)
2. In this case: Running FluxMQ benchmark with Java client that produces:

• Extensive server logs with connection details
• Java client warnings about deprecated methods
• Multiple correlation_id traces
• Benchmark progress output

1. Wait for Claude to process the large output
2. CLI crashes with RangeError before completing the response

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

1.0.127 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

• The error occurs specifically when processing very large text outputs
• This appears to be hitting JavaScript engine string length limits
• The crash makes Claude Code completely unusable until restart
• Issue occurs during the output processing phase, not during the initial command execution
• Similar issues might occur with any command that generates extensive logging or debugging output